Is the World getting warmer?
Average world temperatures are increasing. This is a fact. Is it due to greenhouse gasses or increased energy output from the sun? The amount of energy put out by the sun is not constant. It fluctuates with time and currently we are going through a period of increased output.http://www.cnn.com/2005/TECH/science/02/17/global.warming.reut/index.html
Another perspective or theory is that increased greenhouse gasses are causing extremes in the global weather patterns, and indeed we've seen that quite a bit in the past few years. Areas are having extreme droughts in summer and areas like the American North East are having extreme winters at present. Put another way, if more energy is arriving on the earth's surface it does not just warm things up slightly. More energy is arriving and this energy will manifest itself in some form.
Greater understanding of things is coming to light now that improved data is coming in about ocean temperatures, especially as heat exchange with the oceans is better understood. Clouds have a huge effect, so a possible change in cloudiness over recent decades is perhaps the biggest uncertainty, but even that is probably a response to human influence on the atmosphere.
Overall the signals are now so clear that climate scientists are overcoming their traditional reserve and saying bluntly that the climate is warming and it is a consequence of human activity. The consensus on expected mean temperature rise is about around 1.5 - 5 deg C over this century. With oil consumption rising, it is a good time to be thinking about renewable energy and using the resources we have efficiently.
However, weather is chaotic at the best of times so it is very hard to predict if this is the start of a new pattern or just a normal variation.
A Lenticular Cloud Over New Hampshire Credit & Copyright: J. D. Rufo